Im finally installing my last pair of Savvy control arms, front uppers. When possible in the installation I have used the new hardware for install. If the new hardware would not fit (rear uppers) I re-used stock. On the axle side of the front uppers the new hardware will not fit but I dont really want to re-use this stock fastener. Why is it not a normal hex head? Is there something particular about it or is it simply another fastener with the same purpose as a flag nut, to not have to use two tools to tighten it?